Search results for: clinical chemistry values
Commenced in January 2007
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Edition: International
Paper Count: 10940

Search results for: clinical chemistry values

3170 Development and Characterization of Biscuits Incorporated with Jackfruit (Artocarpus heterophyllus) Seeds and Cassava (Manihot esculenta)

Authors: Elina Brahma Hazarika, Jeuti Basumatary, Deepanka Saikia, Jaydeep Das, Micky Moni D'mary, Fungkha Basumatary

Abstract:

This study includes development of two varieties of biscuits incorporated with: the seeds of Jack fruit (Artocarpus heterophyllus), which post-consumption of it’s pulp, is discarded as a waste, and Cassava (Manihot esculenta) tubers.The jack fruit seeds and cassava were first ground into flour and its proximate and physiochemical properties were studied. The biscuits that were developed incorporating them had 50% wheat flour and 50% jackfruit seed flour and 50% cassava flours as the major composition, apart from the other general ingredients use in making biscuits. Various trials of compositions were made for baking to get the overall desirable acceptability in biscuits through sensory evaluation. Finally, the best composition of ingredients was selected to make the biscuits, and hence studies were done accordingly to compare it with the properties of their respective raw flours. The results showed that the proximate composition of the biscuits fared better than that of their respective flours: There was a decrease in the Moisture content of both Jackfruit Seed Biscuits and Cassava Biscuits to 4.5% and 6.7% than that of their respective raw flours (8 and 12%). Post-baking, there is increase in the percentages of ash, protein, and fibre contents in both Jackfruit Seed Biscuits and Cassava Biscuits; the values being 3% and 3.8%, 13.2% and 3.3%, and 3.2 and 4.1% respectively. Also the total carbohydrate content in Jackfruit Seed Biscuits and Cassava Biscuits were 66.7% and 71.7% respectively. Their sensory evaluation and texture study also yielded a clear review that they have an overall good acceptability.

Keywords: baking, proximate, sensory, texture

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3169 A Prospective Audit to Look into Antimicrobial Prescribing in the Clinical Setting: In a Teaching Hospital in the UK

Authors: Richa Sinha, Mohammad Irfan Javed, Sanjay Singh

Abstract:

Introduction: Good antimicrobial prescribing reduces length of stay in hospital, risk of adverse events, antimicrobial resistance, and unnecessary hospital expenditure. The aim of this prospective audit was to identify any problems with antimicrobial prescribing including documentation of the relevant aspects as well as appropriateness of antibiotics use. The audit was conducted on the surgical wards in a teaching hospital in the UK. Methods: Standards included the indication, duration, choice, and prescription of antibiotic should be in line with current Regional Guidelines and should be clearly documented on the prescription chart. There should be an entry in each patients’ medical record of the diagnosis and indication for each acute antibiotic prescription issued. All prescriptions should clearly document the route, frequency and dose of antibiotic. Data collection was done for 2 weeks in the month of March 2014. A proforma including all the questions above was completed for all the patients. The results were analysed using Excel. Results: 35 patients in total were selected for the audit. 85.7% of patients had indication of antibiotic documented on the prescription chart and 68.5% of patients had indication documented in the notes. The antibiotic used was in line with hospital guidelines in 45.7% of patients, however, in a further 28.5% of patients the reason for the antibiotic prescription was microbiology approved. Therefore, in total 74.2% of patients had been prescribed appropriate antibiotics. The duration of antibiotic was documented in 68.6% of patients and the antibiotic was reviewed in 37.1% of patients. The dose, frequency and route was documented clearly in 100% of patients. Conclusion: Overall, prescribing can be improved on the surgical wards in this hospital. Only 37.1% of patients had clear documentation of a review of antibiotics. It may be that antibiotics have been reviewed but this should be clearly highlighted on the prescription chart or the notes. Failure to review antibiotics can lead to poor patient care and antimicrobial resistance and therefore it is important to address this. It is also important to address the appropriateness of antibiotics as inappropriate antibiotic prescription can lead to failure of treatment as well as antimicrobial resistance. The good points from the audit was that all patients had clear documentation of dose, route and frequency which is extremely important in the administration of antibiotics. Recommendations from this audit included to emphasize good antimicrobial prescribing at induction (twice yearly), an antimicrobial handbook for junior doctors, and re-audit in 6 months time.

Keywords: prescribing, antimicrobial, indication, duration

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3168 Unsupervised Feature Learning by Pre-Route Simulation of Auto-Encoder Behavior Model

Authors: Youngjae Jin, Daeshik Kim

Abstract:

This paper describes a cycle accurate simulation results of weight values learned by an auto-encoder behavior model in terms of pre-route simulation. Given the results we visualized the first layer representations with natural images. Many common deep learning threads have focused on learning high-level abstraction of unlabeled raw data by unsupervised feature learning. However, in the process of handling such a huge amount of data, the learning method’s computation complexity and time limited advanced research. These limitations came from the fact these algorithms were computed by using only single core CPUs. For this reason, parallel-based hardware, FPGAs, was seen as a possible solution to overcome these limitations. We adopted and simulated the ready-made auto-encoder to design a behavior model in Verilog HDL before designing hardware. With the auto-encoder behavior model pre-route simulation, we obtained the cycle accurate results of the parameter of each hidden layer by using MODELSIM. The cycle accurate results are very important factor in designing a parallel-based digital hardware. Finally this paper shows an appropriate operation of behavior model based pre-route simulation. Moreover, we visualized learning latent representations of the first hidden layer with Kyoto natural image dataset.

Keywords: auto-encoder, behavior model simulation, digital hardware design, pre-route simulation, Unsupervised feature learning

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3167 Potassium Acetate - Coconut Shell Activated Carbon for Adsorption of Benzene and Toluene: Equilibrium and Kinetic Studies

Authors: Jibril Mohammed, Usman Dadum Hamza, Abdulsalam Surajudeen, Baba Yahya Danjuma

Abstract:

Considerable concerns have been raised over the presence of volatile organic compounds (VOCs) in water. In this study, coconut shell based activated carbon was produced through chemical activation with potassium acetate (PAAC) for adsorption of benzene and toluene. The porous carbons were characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), proximate analysis, and ultimate analysis and nitrogen adsorption tests. Adsorption of benzene and toluene on the porous carbons were conducted at varying concentrations (50-250 mg/l). The high BET surface area of 622 m2/g and highly heteroporous adsorbent prepared gave good removal efficiencies of 79 and 82% for benzene and toluene respectively, with 32% yield. Equilibrium data were fitted to Langmuir, Freundlich and Temkin isotherms with all the models having R2 > 0.94. The equilibrium data were best represented by the Langmuir isotherm, with maximum adsorption capacity of 192 mg/g and 227 mg/g for benzene and toluene respectively. The Webber and Chakkravorti equilibrium parameter (RL) values are between 0 and 1 confirming the favourability of the Langmuir model. The adsorption kinetics was found to follow the pseudo-second-order kinetic model. The PAAC produced can be used effectively to salvage environmental pollution problems posed by VOCs through a sustainable process.

Keywords: adsorption, equilibrium and kinetics studies, potassium acetate, water treatment

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3166 Change Detection of Vegetative Areas Using Land Use Land Cover of Desertification Vulnerable Areas in Nigeria

Authors: T. Garba, Y. Y. Sabo A. Babanyara, K. G. Ilellah, A. K. Mutari

Abstract:

This study used the Normalized Difference Vegetation Index (NDVI) and maps compiled from the classification of Landsat TM and Landsat ETM images of 1986 and 1999 respectively and Nigeria sat 1 images of 2007 to quantify changes in land use and land cover in selected areas of Nigeria covering 143,609 hectares that are threatened by the encroaching Sahara desert. The results of this investigation revealed a decrease in natural vegetation over the three time slices (1986, 1999 and 2007) which was characterised by an increase in high positive pixel values from 0.04 in 1986 to 0.22 and 0.32 in 1999 and 2007 respectively and, a decrease in natural vegetation from 74,411.60ha in 1986 to 28,591.93ha and 21,819.19ha in 1999 and 2007 respectively. The same results also revealed a periodic trend in which there was progressive increase in the cultivated area from 60,191.87ha in 1986 to 104,376.07ha in 1999 and a terminal decrease to 88,868.31ha in 2007. These findings point to expansion of vegetated and cultivated areas in in the initial period between 1988 and 1996 and reversal of these increases in the terminal period between 1988 and 1996. The study also revealed progressive expansion of built-up areas from 1, 681.68ha in 1986 to 2,661.82ha in 1999 and to 3,765.35ha in 2007. These results argue for the urgent need to protect and conserve the depleting natural vegetation by adopting sustainable human resource use practices i.e. intensive farming in order to minimize persistent depletion of natural vegetation.

Keywords: changes, classification, desertification, vegetation changes

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3165 The Importance of Oral Mucosal Biopsy Selection Site in Areas of Field Change: A Case Report

Authors: Timmis W., Simms M., Thomas C.

Abstract:

This case discusses the management of two floors of mouth (FOM) Squamous Cell Carcinomas (SCC) not identified upon initial biopsy. A 51 year-old male presented with right FOM erythroleukoplakia. Relevant medical history included alcoholic dependence syndrome and alcoholic liver disease. Relevant drug therapy encompassed acamprosate, folic acid, hydroxocobalamin and thiamine. The patient had a 55.5 pack-year smoking history and alcohol dependence from age 14, drinking 16 units/day. FOM incisional biopsy and histopathological analysis diagnosed Carcinoma in situ. Treatment involved wide local excision. Specimen analysis revealed two separate foci of pT1 moderately differentiated SCCs. Carcinoma staging scans revealed no pathological lymphadenopathy, no local invasion or metastasis. SCCs had been excised in completion with narrow margins. MDT discussion concluded that in view of the field changes it would be difficult to identify specific areas needing further excision, although techniques such as Lugol’s Iodine were considered. Further surgical resection, surgical neck management and sentinel lymph node biopsy was offered. The patient declined intervention, primary management involved close monitoring alongside alcohol and smoking cessation referral. Narrow excisional margins can increase carcinoma recurrence risk. Biopsy failed to identify SCCs, despite sampling an area of clinical concern. For gross field change multiple incisional biopsies should be considered to increase chance of accurate diagnosis and appropriate treatment. Coupling of tobacco and alcohol has a synergistic effect, exponentially increasing the relative risk of oral carcinoma development. Tobacco and alcoholic control is fundamental in reducing treatment‑related side effects, recurrence risk and second primary cancer development.

Keywords: alcohol dependence, biopsy, oral carcinoma, tobacco

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3164 Impact of Drought on Agriculture in the Upper Middle Gangetic Plain in India

Authors: Reshmita Nath

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In this study, we investigate the spatiotemporal characteristics of drought in India and its impact on agriculture during the summer season (April to September). For our analysis, we have used Standardized Precipitation Evapotranspiration Index (SPEI) datasets between 1982 and 2012 at six-month timescale. Based on the criteria SPEI<-1 we obtain the vulnerability map and have found that the Humid subtropical Upper Middle Gangetic Plain (UMGP) region is highly drought prone with an occurrence frequency of 40-45%. This UMGP region contributes at least 18-20% of India’s annual cereal production. Not only the probability, but the region becomes more and more drought-prone in the recent decades. Moreover, the cereal production in the UMGP has experienced a gradual declining trend from 2000 onwards and this feature is consistent with the increase in drought affected areas from 20-25% to 50-60%, before and after 2000, respectively. The higher correlation coefficient (-0.69) between the changes in cereal production and drought affected areas confirms that at least 50% of the agricultural (cereal) losses is associated with drought. While analyzing the individual impact of precipitation and surface temperature anomalies on SPEI (6), we have found that in the UMGP region surface temperature plays the primary role in lowering of SPEI. The linkage is further confirmed by the correlation analysis between the SPEI (6) and surface temperature rise, which exhibits strong negative values in the UMGP region. Higher temperature might have caused more evaporation and drying, which therefore increases the area affected by drought in the recent decade.

Keywords: drought, agriculture, SPEI, Indo-Gangetic plain

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3163 Assessment of Acute Cardiovascular Responses to Moderate and Vigorous Intensity Aerobic Exercises in Sedentary Adults and Amateur Athletes

Authors: Caner Yilmaz, Zuhal Didem Takinaci

Abstract:

Introduction: Today, our knowledge about the effects of physical activity performed at the different intensity of the cardiovascular system are still not clear. Therefore, to contribute to the literature, in our study, sedentary individuals and amateur athletes were assessed in a single session with the aim of evaluating the cardiovascular effects of the moderate and severe exercise. Methods: 80 participants (40 amateur athletes and 40 sedentary, young adults) participated in our study. Participants were divided into two groups: amateur athletes (mean age: 25.0 ± 3.6 yrs) and sedentary in group II (mean age: 23.8 ± 3.7 yrs). Participants in both groups were assessed twice, namely, firstly, at moderate intensity (5km/h 30 min. walking) and secondly at the vigorous intensity (8km/h 20 min. jogging). Participants’ SBP (Systolic Blood Pressure), DBP (Diastolic Blood Pressure), HR (Heart Rate), SpO₂ (Oxygen Saturation), BT (Body Temperature) and RR (Respiratory Rate) were measured. Results: In our study, the findings showed that after moderate-intensity aerobic exercise, change in SBP, DBP, and SpO₂ were significantly higher in Group II (p < 0.05). After the severe intensity aerobic exercises, change in SBP, SpO₂, HR, and RR was significantly higher in Group II (p < 0.05). The BORG score of Group II was significantly higher after both moderate and severe intensity aerobic exercise (p < 0.05). Conclusion: The cardiovascular responses of amateur athletes were closer to initial values, and the differences between the two groups were increased in direct proportion to the intensity of the exercise. Both exercise intensities could be adequate.

Keywords: aerobic, exercise, sedantary, cardi̇ovascular

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3162 Insulin-Producing Cells from Adult Human Bone Marrow Mesenchymal Stem Cells Control Chemically-Induced Diabetes in Dogs

Authors: Maha Azzam, Mahmoud Gabr, Mahmoud Zakaria, Ayman Refaie, Amani Ismail, Sherry Khater, Sylvia Ashamallah, Mohamed Ghoniem

Abstract:

Evidence was provided that human bone marrow-derived mesenhymal stem cells (HBM-MSCs) could be differentiated to form insulin-producing cells (IPCs). Transplantation of these cells was able to cure chemically-induced diabetes in nude mice. The efficacy of these cells to control diabetes in large animals was carried out to evaluate the sufficient number of cells needed/Kg body weight and to determine the functional longevity in vivo. Materials/Methods: Ten male mongrel dogs weighing 15-20 Kg were used in this study. Diabetes was chemically-induced in 7 dogs by a mixture of alloxan and streptozotocin. Three non-diabetic served as normal controls. Differentiated HBM-MSCs (5 million/Kg) were encapsulated in theracyte capsules and transplanted beneath the rectus sheath. Each dog received 2 capsules. One dog died 4 days postoperative from inhalation pneumonia. The remaining 6 dogs were followed up for 6-18 months. Results: Four dogs became normoglycemic within 6-8 weeks with normal glucose tolerance curves providing evidence that the transplanted cells were glucose-sensitive and insulin-responsive. In the remaining 2 dogs, fasting blood glucose was reduced but did not reach euglycemic levels. The sera of all transplanted dogs contained human insulin and c-peptide but negligible levels of canine insulin. When the HBM-MSCs loaded capsules were removed, rapid return of diabetic state was noted. The harvested capsules were examined by immunofluorescence. IPCs were seen and co-expression of with c-peptide was confirmed. Furthermore, all the pancreatic endocrine genes were expressed by the transplanted cells. Conclusions: This study provided evidence that theracyte capsules could protect the xenogenic HBM-MSCs from the host immune response. This is an important issue when clinical stem cell therapy is considered for definitive treatment for T1DM.

Keywords: diabetes, mesenchymal stem cells, dogs, Insulin-producing cells

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3161 KAP Study on Breast Cancer Among Women in Nirmala Educational Institutions-A Prospective Observational Study

Authors: Shaik Asha Begum, S. Joshna Rani, Shaik Abdul Rahaman

Abstract:

INTRODUCTION: Breast cancer is a disease that creates in breast cells. "KAP" study estimates the Knowledge, Attitude, and Practices of a local area. More than 1.5 million ladies (25% of all ladies with malignancy) are determined to have bosom disease consistently all through the world. Understanding the degrees of Knowledge, Attitude and Practice will empower a more effective cycle of mindfulness creation as it will permit the program to be custom-made all the more properly to the necessities of the local area. OBJECTIVES: The objective of this study is to assess the knowledge on signs and symptoms, risk factors, provide awareness on the practicing of the early detection techniques of breast cancer and provide knowledge on the overall breast cancer including preventive techniques. METHODOLOGY: This is an expressive cross-sectional investigation. This investigation of KAP was done in the Nirmala Educational Institutions from January to April 2021. A total of 300 participants are included from women students in pharmacy graduates & lecturers, and also from graduates other than the pharmacy. The examiners are taken from the BCAM (Breast Cancer Awareness Measure), tool compartment (Version 2). RESULT: According to the findings of the study, the majority of the participants were not well informed about breast cancer. A lump in the breast was the most commonly mentioned sign of breast cancer, followed by pain in the breast or nipple. The percentage of knowledge related to the breast cancer risk factors was also very less. The correct answers for breast cancer risk factors were radiation exposure (58.20 percent), a positive family history (47.6 percent), obesity (46.9 percent), a lack of physical activity (43.6 percent), and smoking (43.2 percent). Breast cancer screening, on the other hand, was uncommon (only 30 and 11.3 percent practiced clinical breast examination and mammography respectively). CONCLUSION: In this study, the knowledge on the signs and symptoms, risk factors of breast cancer - pharmacy graduates have more knowledge than the non-pharmacy graduates but in the preventive techniques and early detective tools of breast cancer -had poor knowledge in the pharmacy and non-pharmacy graduate. After the awareness program, pharmacy and non-pharmacy graduates got supportive knowledge on the preventive techniques and also practiced the early detective techniques of breast cancer.

Keywords: breast cancer, mammography, KAP study, early detection

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3160 Prompting and Encouraging Community Hydration through Education: A Realist Review and Evaluation Exploring Hydration in a Population at Risk of Frailty

Authors: Mark Davies, Carolyn Wallace, Christina Lloydwin, Tom Powell

Abstract:

Background: Frailty is increasingly recognized as a public health problem within an aging population. It is often characterized as an accumulation of clinical symptoms with progressive decline. We contend that dehydration is potentially the missing link driving the cycle of frailty; it contributes to malnutrition and cognitive decline and is a risk factor for other conditions. Frailty may also impact on fluid intake in cognitively intact older adults, indicating the cyclical nature of dehydration contributing to increasing frailty. Aim: To examine the relationships between fluid, hydration, and frailty in older adults in order to determine what works, for whom, how, why, and in what circumstances. Methods: A Realist Synthesis was first undertaken with n=50 studies, leading to the development of a Refined Programme Theory (RPT) articulating what hydration interventions work, for whom, to what degree, in what contexts, and how & why. Within the subsequent evaluation, the RPT was further confirmed/refuted/refined following semi-structured interviews with n=8 participants (healthcare professionals and patients). The RAMESES Quality Standards were followed throughout the study. Results: The Refined Programme Theory (RPT) highlighted three factors that result in optimized hydration for frail older people, i.e., Developing an Understanding Around Hydration, Empowering Participation, and System Reconfiguration. Our RPT indicates that hydration interventions work by developing an understanding of the importance of hydration, mitigating physical & cognitive barriers, increasing the agency of the patient, using a prompting process to reinforce drinking behavior, and routinizing hydration as a dimension of overall care. Conclusion: The study indicates that a greater understanding of the importance of hydration is required for all parties. Patients also require physical and psychological support if they are to be active agents in meeting their hydration needs. At a wider ‘system’ level, organizations must work in an integrated manner introducing processes that enable continuing professional development (CPD), encourage ongoing holistic assessment, and routinize hydration support.

Keywords: frailty, dehydration, older adults, realist review, realist evaluation

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3159 Tom Stoppard: The Amorality of the Artist

Authors: Majeed Mohammed Midhin, Clare Finburgh

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To maintain a healthy balanced loyalty between art and politics posits a debatable issue. The artist is always on the look out for the potential tension between those two realms. Therefore, one of the most painful dilemmas the artist finds is how to function in a society without sacrificing the aesthetic values of his/her work. In other words, the life-long awareness of failure which derives from the concept of the artist as caught between unflattering social realities and the need to invent genuine art forms becomes a fertilizing soil for the artists to dig deep into its origin. Thus, within the framework of this dilemma, the question of the responsibility of the artist and the relationship of the art to politics will be illuminating. The present paper tackles the idea of the amorality of the artist in selected plays by Tom Stoppard. However, Stoppard’s awareness of his situation as a refugee has led him to keep at a distance from politics. He tried hard to avoid any intervention into the realms of political debate, especially in his earliest work. On the one hand, it is not meant that he did not interest in politics as such, but rather he preferred to question it than to create a fixed ideological position. On the other hand, Stoppard’s refusal to intervene in politics is ascribed to his feeling of gratitude to Britain where he settled. As a result, Stoppard has frequently been criticized for a lack of political engagement and also for not leaning too much for the left when he does engage. His reaction to these public criticisms finds expression in his self-conscious statements which defensively stressed the artifice of his work. He, like Oscar Wilde thinks that the responsibility of the artist is devoted to the realm of his/her art. Consequently, his consciousness for the role of the artist is truly reflected in his two plays, Artist Descending a Staircase(1972) and Travesties(1974).

Keywords: amorality, dilemma, aesthetic, responsibility of the artist, political theatre

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3158 Improvement of Total Phenolic Contents and Anti-oxidative Properties of Ricegrass (Oryza sativa L.) using Selenium Bio-fortification

Authors: Rattanamanee Chomchan, Sunisa Siripongvutikorn, Panupong Puttarak

Abstract:

Ricegrass or young rice sprouts can be introduced as one of functional product since cereal sprouts have been much interested in this era due to their high nutritive values. Bio-fortification of selenium is one strategy to improve plant bioactive compounds. However, the level of selenium used are varied among species of plants, hence, the proper level need to be investigated. In this current study, influence of selenium bio-fortification hydroponically in the form of sodium selenite following the range 0, 10, 20, 30 and 40 mg Se/L on growth characteristics, selenium content, total extractable phenolic content (TPC) accumulation, lipid peroxidation and anti-oxidative properties of ricegrass were investigated. Results revealed that selenium bio-fortified exogenously increased the accumulation of selenium in ricegrass by 5.3 fold at 40 mg Se/L treatment without significant changes in leaves biomass at harvesting day while root part weight were slightly decreased when increased selenium level, respectively. Selenium at low concentration (10 and 20 mg Se/L) can stimulate the production of phenolic compounds and antioxidant activities in young ricegrass as measured by DPPH, ABTS and FRAP assay. Conversely, higher level of selenium fortification reduced the accumulation of phenolics in ricegrass afterward by acting as pro-oxidant. Moreover, highest significant reduction in oxidative stress, measured as malondialdehyde content was also observed at 20 mg Se/L treatment which in correlation to high TPC and antioxidant activities. In conclusion, selenium bio-fortification can be used as a technique to improve precious to ricegrass.

Keywords: antioxidant activities, bio-fortification, ricegrass, selenium

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3157 Evaluation of the Power Generation Effect Obtained by Inserting a Piezoelectric Sheet in the Backlash Clearance of a Circular Arc Helical Gear

Authors: Barenten Suciu, Yuya Nakamoto

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Power generation effect, obtained by inserting a piezo- electric sheet in the backlash clearance of a circular arc helical gear, is evaluated. Such type of screw gear is preferred since, in comparison with the involute tooth profile, the circular arc profile leads to reduced stress-concentration effects, and improved life of the piezoelectric film. Firstly, geometry of the circular arc helical gear, and properties of the piezoelectric sheet are presented. Then, description of the test-rig, consisted of a right-hand thread gear meshing with a left-hand thread gear, and the voltage measurement procedure are given. After creating the tridimensional (3D) model of the meshing gears in SolidWorks, they are 3D-printed in acrylonitrile butadiene styrene (ABS) resin. Variation of the generated voltage versus time, during a meshing cycle of the circular arc helical gear, is measured for various values of the center distance. Then, the change of the maximal, minimal, and peak-to-peak voltage versus the center distance is illustrated. Optimal center distance of the gear, to achieve voltage maximization, is found and its significance is discussed. Such results prove that the contact pressure of the meshing gears can be measured, and also, the electrical power can be generated by employing the proposed technique.

Keywords: circular arc helical gear, contact problem, optimal center distance, piezoelectric sheet, power generation

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3156 An Inverse Approach for Determining Creep Properties from a Miniature Thin Plate Specimen under Bending

Authors: Yang Zheng, Wei Sun

Abstract:

This paper describes a new approach which can be used to interpret the experimental creep deformation data obtained from miniaturized thin plate bending specimen test to the corresponding uniaxial data based on an inversed application of the reference stress method. The geometry of the thin plate is fully defined by the span of the support, l, the width, b, and the thickness, d. Firstly, analytical solutions for the steady-state, load-line creep deformation rate of the thin plates for a Norton’s power law under plane stress (b → 0) and plane strain (b → ∞) conditions were obtained, from which it can be seen that the load-line deformation rate of the thin plate under plane-stress conditions is much higher than that under the plane-strain conditions. Since analytical solution is not available for the plates with random b-values, finite element (FE) analyses are used to obtain the solutions. Based on the FE results obtained for various b/l ratios and creep exponent, n, as well as the analytical solutions under plane stress and plane strain conditions, an approximate, numerical solutions for the deformation rate are obtained by curve fitting. Using these solutions, a reference stress method is utilised to establish the conversion relationships between the applied load and the equivalent uniaxial stress and between the creep deformations of thin plate and the equivalent uniaxial creep strains. Finally, the accuracy of the empirical solution was assessed by using a set of “theoretical” experimental data.

Keywords: bending, creep, thin plate, materials engineering

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3155 Assessment of Alteration in High Density Lipo Protein, Apolipoprotein A1, Serum Glutamic Pyruvic Transaminase and Serum Glutamic Oxaloacetic Transaminase in Oral Submucous Fibrosis Patients

Authors: Marina Lazar Chandy, N. Kannan, Rajendra Patil, Vinod Mathew, Ajmal Mohamed, P. K. Sreeja, Renju Jose

Abstract:

Introduction- Arecoline, a major constituent of arecanut has shown to have some effect on liver. The use of arecanut is found to be the most common etiological factor for the development of Oral Submucous fibrosis (O.S.M.F). The effect of arecanut usage on liver in patients with O.S.M.F needs to be assessed. Lipids play a role in structural maintenance of cell. Alterations of lipid profile were noted in cancer patients. O.S.M.F being a precancerous lesion can have some effect on the level of lipids in the body. Objectives: This study was done to assess the alterations in liver enzymes (Serum Glutamic Pyruvic Transaminase(S.G.P.T ,Serum Glutamic Oxaloacetic Transaminase(S.G.O.T)) and lipid metabolism (High Density Lipoprotien(H.D.L) and Apo Lipoprotien A1 (Apo A1)) in patients with O.S.M.F. Methods-130 patients were taken for the study,100 patients with O.S.M.F and 30 as control group without O.S.M.F. Fasting blood sugar levels were taken, centrifuged and analyzed for S.G.P.T,S.G.O.T, H.D.L and Apo A1 using semi automated spectrophotometer. Results: After statistical analysis, it was concluded that there is an elevation of levels of S.G.P.T, S.G.O.T, and decreased levels of H.D.L, Apo A1 for O.S.M.F group when compared with control group. With increased grade of O.S.M.F. and duration of habit, S.G.P.T. & S.G.O.T. increased whereas, H.D.L. & Apo A1 decreased. All the values were statistically significant at p<0.01.

Keywords: apolipoprotien A1, high density lipoprotien, oral submucous fibrosis, serum glutamic oxaloacetic transaminase

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3154 Evaluation of Chemical Compositions and Biological Activities of Five Essential Oils

Authors: G. Ozturk, B. Demirci

Abstract:

It is well known that essential oils used for therapeutic purposes for many years. In this study, five different Pharmacopoeia grade essential oils (Achillea millefolium L., Pimpinella anisum L., Matricaria recutita L., Eucalyptus globulus L., Salvia officinalis L.) which obtained from commercial sources were evaluated for chemical compositions, synergistic antimicrobial activities, and lipoxygenase enzyme inhibitions. Volatile components were determined by gas chromatography/flame ionization detector and gas chromatography/mass spectrometer, simultaneously. The potential antimicrobial activity of essential oils was tested against oral pathogenic standard strains such as Streptococcus mutans, Streptococcus sanguinis, Staphylococcus aureus, Corynebacterium striatum, Candida albicans and Candida krusei by broth microdilution methods. Ciprofloxacin and ketoconazole were used positive controls. It has been observed that the essential oils tested have average inhibitory antimicrobial activity against oral pathogens with a Minimum Inhibition Concentration of 20-0.625 mg/mL. The active essential oils have been combined with antibiotics and synergistic effects have been evaluated by Checkerboard method. ƩFIC values were determined. In combination with antibiotics M. recutita essential oil has been shown to have a synergistic effect against S. aureus in combination with tetracycline (ƩFIC 0.46). In addition, 5-LOX inhibitory activity was measured by modifying the spectrophotometric method developed by Baylac and Racine. As a result, 5-LOX % inhibition of S. officinalis, E. globulus and M. recutita were calculated as 34.0 ± 6.66, 72.7 ± 2.78 and 27.7 ± 0.60, respectively.

Keywords: antimicrobial activity, essential oils, synergistic activity, 5-lipoxygenase inhibition

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3153 Hybrid GNN Based Machine Learning Forecasting Model For Industrial IoT Applications

Authors: Atish Bagchi, Siva Chandrasekaran

Abstract:

Background: According to World Bank national accounts data, the estimated global manufacturing value-added output in 2020 was 13.74 trillion USD. These manufacturing processes are monitored, modelled, and controlled by advanced, real-time, computer-based systems, e.g., Industrial IoT, PLC, SCADA, etc. These systems measure and manipulate a set of physical variables, e.g., temperature, pressure, etc. Despite the use of IoT, SCADA etc., in manufacturing, studies suggest that unplanned downtime leads to economic losses of approximately 864 billion USD each year. Therefore, real-time, accurate detection, classification and prediction of machine behaviour are needed to minimise financial losses. Although vast literature exists on time-series data processing using machine learning, the challenges faced by the industries that lead to unplanned downtimes are: The current algorithms do not efficiently handle the high-volume streaming data from industrial IoTsensors and were tested on static and simulated datasets. While the existing algorithms can detect significant 'point' outliers, most do not handle contextual outliers (e.g., values within normal range but happening at an unexpected time of day) or subtle changes in machine behaviour. Machines are revamped periodically as part of planned maintenance programmes, which change the assumptions on which original AI models were created and trained. Aim: This research study aims to deliver a Graph Neural Network(GNN)based hybrid forecasting model that interfaces with the real-time machine control systemand can detect, predict machine behaviour and behavioural changes (anomalies) in real-time. This research will help manufacturing industries and utilities, e.g., water, electricity etc., reduce unplanned downtimes and consequential financial losses. Method: The data stored within a process control system, e.g., Industrial-IoT, Data Historian, is generally sampled during data acquisition from the sensor (source) and whenpersistingin the Data Historian to optimise storage and query performance. The sampling may inadvertently discard values that might contain subtle aspects of behavioural changes in machines. This research proposed a hybrid forecasting and classification model which combines the expressive and extrapolation capability of GNN enhanced with the estimates of entropy and spectral changes in the sampled data and additional temporal contexts to reconstruct the likely temporal trajectory of machine behavioural changes. The proposed real-time model belongs to the Deep Learning category of machine learning and interfaces with the sensors directly or through 'Process Data Historian', SCADA etc., to perform forecasting and classification tasks. Results: The model was interfaced with a Data Historianholding time-series data from 4flow sensors within a water treatment plantfor45 days. The recorded sampling interval for a sensor varied from 10 sec to 30 min. Approximately 65% of the available data was used for training the model, 20% for validation, and the rest for testing. The model identified the anomalies within the water treatment plant and predicted the plant's performance. These results were compared with the data reported by the plant SCADA-Historian system and the official data reported by the plant authorities. The model's accuracy was much higher (20%) than that reported by the SCADA-Historian system and matched the validated results declared by the plant auditors. Conclusions: The research demonstrates that a hybrid GNN based approach enhanced with entropy calculation and spectral information can effectively detect and predict a machine's behavioural changes. The model can interface with a plant's 'process control system' in real-time to perform forecasting and classification tasks to aid the asset management engineers to operate their machines more efficiently and reduce unplanned downtimes. A series of trialsare planned for this model in the future in other manufacturing industries.

Keywords: GNN, Entropy, anomaly detection, industrial time-series, AI, IoT, Industry 4.0, Machine Learning

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3152 Development of a Double Coating Technique for Recycled Concrete Aggregates Used in Hot-mix Asphalt

Authors: Abbaas I. Kareem, H. Nikraz

Abstract:

The use of recycled concrete aggregates (RCAs) in hot-mix asphalt (HMA) production could ease natural aggregate shortage and maintain sustainability in modern societies. However, it was the attached cement mortar and other impurities that make the RCAs behave differently than high-quality aggregates. Therefore, different upgrading treatments were suggested to enhance its properties before being used in HMA production. Disappointedly, some of these treatments had caused degradation to some RCA properties. In order to avoid degradation, a coating technique is developed. This technique is based on combining of two main treatments, so it is named as double coating technique (DCT). Dosages of 0%, 20%, 40% and 60% uncoated RCA, RCA coated with Cement Slag Paste (CSP), and Double Coated Recycled Concrete Aggregates (DCRCAs) in place of granite aggregates were evaluated. The results indicated that the DCT improves strength and reduces water absorption of the DCRCAs compared with uncoated RCAs and RCA coated with CSP. In addition, the DCRCA asphalt mixtures exhibit stability values higher than those obtained for mixes made with granite aggregates, uncoated RCAs and RCAs coated with CSP. Also, the DCRCA asphalt mixtures require less bitumen to achieve the optimum bitumen content (OBC) than those manufactured with uncoated RCA and RCA-coated with CSP. Although the results obtained were encouraging, more testing is required in order to examine the effect of the DCT on performance properties of DCRCA- asphalt mixtures such as rutting and fatigue.

Keywords: aggregate crashed value, double coating technique, hot mix asphalt, Marshall parameters, recycled concrete aggregates

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3151 Traditional Knowledge on Living Fences in Andean Linear Plantations

Authors: German Marino Rivera

Abstract:

Linear plantations are a common practice in several countries as living fences (LF) delimiting agroecosystems. They are composed of multipurpose perennial woods that provide assets, protection, and supply services. However, not much is known in some traditional communities like the Andean region, including the species composition and the social and ecological benefits of the species used. In the High Andean Colombian region, LF seems to be very typical and diverse. This study aimed to analyze the traditional knowledge about LF systems, including the species composition and their uses in rural communities of Alto Casanare, Colombia. Field measurements, interviews, guided tours, and species sampling were carried out in order to describe traditional practices and the species used in the LF systems. The use values were estimated through the Coefficient of Importance of the Species (CIS). A total of 26 farms engage in LF practices, covering an area of 9283.3 m. In these systems, 30 species were identified, belonging to 23 families. Alnus acuminata was the specie with the highest CIS. The species presented multipurpose uses for both economic and ecological purposes. The transmission of knowledge (TEK) about the used species is very heterogeneous among the farmers. Many species used were not documented, with reciprocal gaps between the literature and traditional species uses. Exchanging this information would increase the species' versatility, the socioeconomic aspects of these communities, increases the agrobiodiversity and ecological services provided by LF. The description of the TEK on LF provides a better understanding of the relationship of these communities with the natural resources, pointing out creative approaches to achieve local environment conservation in these agroecosystems and promoting socioeconomic development.

Keywords: ethnobotany, living fences, traditional communities, agroecology

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3150 Preservation of Traditional Algerian Sausage Against Microbial Activity by the Garlic (Allium Sativum L.)

Authors: Abed Hannane, Rouag Noureddine

Abstract:

The present study aims to evaluate the association of fresh garlic (Allium sativum L.) and storage at 4°C in preserving the microbiological, nutritional, and sanitary quality of Merguez-type sausages prepared and sold locally from meat offal. The analysis focused on the evaluation of the microbiological quality of fifteen samples randomly taken from several butcheries in the wilaya of BBA, eastern Algeria. The bacteriological analysis revealed the presence of 6.88.10⁵ CFU/g of total aerobic bacteria, 5.39.10⁵ CFU/g of total coliforms, 2.23.10⁵ CFU/g of fecal coliforms, 2.43.103 CFU/g of Escherichia coli and 1.8.10⁵ CFU/g of coagulase-positive staphylococci, values higher than Algerian standards. The addition of fresh garlic as an antibacterial preservative at concentrations of 0.06, 0.12, 0.18, and 0.24 g/g to ground beef samples and stored in the refrigerator at 4°C for 15 days. The addition of garlic to Merguez made it possible to significantly reduce the presence of different bacterial groups during their refrigerated storage, compared to untreated meat, bringing it below the standards defined in the matter. Thus, the use of garlic as a food additive at a concentration of 0.12 g/g was sufficient to obtain levels according to Algerian standards equal to 1.8.10⁴ CFU/g of total aerobic bacteria, 9.48.10³ CFU/ g of total coliforms, 3.68.10³ UFC/g fecal coliforms, 4.56.10² UFC/g of E.coli 2.39.10⁴ UFC/g of coagulase-positive staphylococci. It is clear that thanks to the addition of garlic to Merguez, the sanitary quality has been improved by reducing the aerobic bacterial load and increasing the shelf life at 4°C.

Keywords: antimicrobial effect, garlic, sausage, storage

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3149 Lidocaine-Bupivacaine Block Improve Analgesia in Cats Undergoing Orchiectomy

Authors: T. C. Ng, R. Radzi, T. K. Ng, H. C. Chen

Abstract:

The analgesic effects of lidocaine-bupivacaine block in cats undergoing routine orchiectomy were determined in this controlled, randomized, and blinded study. Twelve cats were randomly assigned to two groups. Cats in local block group received subcutaneous infiltration of 1 mg/kg of 2% lidocaine and 1 mg/kg of 0.5% bupivacaine into the scrotal sac. Cats in control group received equivolume of saline. Both groups were induced with mixture of ketamine (15 mg/kg) and acepromazine (0.1 mg/kg) intramuscularly and maintained on sevoflurane via facemask. Non-invasive blood pressures (BP), heart (HR), and respiratory rate (RR) were measured intra-operatively at specific events. Post-operatively, all cats received meloxicam, 0.2 mg/kg subcutaneously. Pain scores were determined at 4, 8, and 24 hours postoperatively. Mechanical pressure thresholds (MPT) at the perineum and metatarsus were determined at 2, 4, 8, and 24 hours postoperatively. Intra-operatively, the BP and HR tended to be higher in the control group. The increment in HR peaked during traction and autoligation of the spermatic cord in the control group. There was no treatment difference in RR. Post-operatively, pain scores in the group given local blocks were lower than the control group at 4 hour post-operation. There was no treatment difference in the post-operative HR, RR, BP and MPT values. In conclusion, subcutaneous infiltration of lidocaine-bupivacaine into the scrotal sac before orchiectomy improved intra-operative hemodynamic stability and provided better analgesia up to 4 hours post-surgery.

Keywords: analgesia, bupivacaine, cat, lidocaine, local block, orchiectomy

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3148 Value of Willingness to Pay for a Quality-Adjusted Life Years Gained in Iran; A Modified Chained-Approach

Authors: Seyedeh-Fariba Jahanbin, Hasan Yusefzadeh, Bahram Nabilou, Cyrus Alinia, Cyrus Alinia

Abstract:

Background: Due to the lack of a constant Willingness to Pay per one additional Quality Adjusted Life Years gained based on the preferences of Iran’s general public, the cost-efectiveness of health system interventions is unclear and making it challenging to apply economic evaluation to health resources priority setting. Methods: We have measured this cost-efectiveness threshold with the participation of 2854 individuals from fve provinces, each representing an income quintile, using a modifed Time Trade-Of-based Chained-Approach. In this online-based empirical survey, to extract the health utility value, participants were randomly assigned to one of two green (21121) and yellow (22222) health scenarios designed based on the earlier validated EQ-5D-3L questionnaire. Results: Across the two health state versions, mean values for one QALY gain (rounded) ranged from $6740-$7400 and $6480-$7120, respectively, for aggregate and trimmed models, which are equivalent to 1.35-1.18 times of the GDP per capita. Log-linear Multivariate OLS regression analysis confrmed that respondents were more likely to pay if their income, disutility, and education level were higher than their counterparts. Conclusions: In the health system of Iran, any intervention that is with the incremental cost-efectiveness ratio, equal to and less than 7402.12 USD, will be considered cost-efective.

Keywords: willingness to Pay, QALY, chained-approach, cost-efectiveness threshold, Iran

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3147 Quality of Life of Elderly People in Urban West Bengal, India

Authors: Debalina Datta, Pratyaypratim Datta, Kunal Kanti Majumdar

Abstract:

Introduction: In India 8.1% of total population is elderly. The standard of living and meaningfulness of life are indirectly measured by assessing quality of life of elderly. So, it is important to improve quality of life. Quality of life is an individual’s understanding of his/ her life situation with respect to his/ her values and cultural context as well as in relation to his/her goals, expectations and concerns. The present study was planned to assess the quality of life of geriatric people in urban West Bengal, India. Materials and methods: It was a community based cross sectional observational study conducted among people aged 60 years and above in Kolkata and Sonarpur region of West Bengal, India. Data collection was done by house to house visit using Quality of Life- BREF questionnaire (WHOQOL-BERF) developed by WHO. Analysis of quality of life of physical, psychological, social relationship and environmental domain was done using SPSS (version 16.0). Results: Transformed score (0-100 scale) was used for each domain. Mean of physical, psychological, social relationship and environmental domain were found to be 42.25, 40.84, 39.62 and 48.36 respectively. There was no significant difference in score between Kolkata and Sonarpur people in any domain except social relationship domain, where people living at Sonarpur scored significantly better. Conclusion: Rehabilitation of old age people can be done by improving their quality of life. Social interaction with people of all ages, allowing them to take important family decision, engaging them in different social activities can help a lot.

Keywords: quality of life, elderly, Urban West Bengal, India

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3146 Tablet Computer Based Cognitive Rehabilitation Program, Injini, for Children with Cognitive Impairment

Authors: Eun Jae Ko, In Young Sung, Eui Soo Joeng

Abstract:

Cognitive impairment is commonly encountered problem in children with various clinical diseases, including Down syndrome, autism spectrum disorder, brain injury, and others. Cognitive impairment limits participation in education and society, and this further hinders development in cognition. However, young children with cognitive impairment tend not to respond well to traditional cognitive treatments, therefore alternative treatment choices are need. As a cognitive training program, touch screen technology can easily be applied to very young children by involving visual and auditory support. Injini was developed as tablet computer based cognitive rehabilitation program for young children or individuals with severe cognitive impairment, which targeted on cognitive ages of 18 to 36 months. The aim of this study was to evaluate the efficacy of a tablet computer based cognitive rehabilitation program (Injini) for children with cognitive impairment. 38 children between cognitive ages of 18 to 36 months confirmed by cognitive evaluations were recruited and randomly assigned to the intervention group (n=20) and the control group (n=18). The intervention group received tablet computer based cognitive rehabilitation program (Injini) for 30 minutes per session, twice a week, over a period of 12 weeks, in addition to the traditional rehabilitation program. The control group received traditional rehabilitation program only. Mental score of Bayley Scales of Infant Development II (BSID II), Pediatric Evaluation of Disability Inventory (PEDI), Laboratory Temperament Assessment Battery (Lab-TAB), Early Childhood Behavior Questionnaire (ECBQ), and Goal Attainment Scale (GAS) were evaluated before and after 12 weeks of therapeutic intervention. When comparing the baseline characteristics, there was no significant difference between the two groups in the measurements of cognitive function. After 12 weeks of treatment, both group showed improvements in all measurements. However, in comparison of improvements after treatment, the intervention group showed more improvements in the mental score of BSID II, social function domain of PEDI, observation domain of Lab-TAB, and GAS, as compared to the control group. Application of the tablet computer based cognitive rehabilitation program (Injini) would be beneficial for improvement of cognitive function in young children with cognitive impairment.

Keywords: cognitive therapy, computer-assisted therapy, early intervention, tablets

Procedia PDF Downloads 284
3145 Performance Analysis of High Temperature Heat Pump Cycle for Industrial Process

Authors: Seon Tae Kim, Robert Hegner, Goksel Ozuylasi, Panagiotis Stathopoulos, Eberhard Nicke

Abstract:

High-temperature heat pumps (HTHP) that can supply heat at temperatures above 200°C can enhance the energy efficiency of industrial processes and reduce the CO₂ emissions connected with the heat supply of these processes. In the current work, the thermodynamic performance of 3 different vapor compression cycles, which use R-718 (water) as a working medium, have been evaluated by using a commercial process simulation tool (EBSILON Professional). All considered cycles use two-stage vapor compression with intercooling between stages. The main aim of the study is to compare different intercooling strategies and study possible heat recovery scenarios within the intercooling process. This comparison has been carried out by computing the coefficient of performance (COP), the heat supply temperature level, and the respective mass flow rate of water for all cycle architectures. With increasing temperature difference between the heat source and heat sink, ∆T, the COP values decreased as expected, and the highest COP value was found for the cycle configurations where both compressors have the same pressure ratio (PR). The investigation on the HTHP capacities with optimized PR and exergy analysis has also been carried out. The internal heat exchanger cycle with the inward direction of secondary flow (IHX-in) showed a higher temperature level and exergy efficiency compared to other cycles. Moreover, the available operating range was estimated by considering mechanical limitations.

Keywords: high temperature heat pump, industrial process, vapor compression cycle, R-718 (water), thermodynamic analysis

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3144 Dermatophytoses: Spectrum Evolution of Dermatophytes in Sfax, Tunisia, Between 1999 and 2019

Authors: Khemakhem Nahed, Hammami Fatma, Trabelsi Houaida, Neji Sourour, Sellami Hayet, Makni Fattouma, Turki Hamida, Ayadi Ali

Abstract:

Dermatophytoses are considered a public health problem and represent 10% of dermatological consultations in our region. Their epidemiology is influenced by various factors, such as lifestyle, human migration patterns, changes in the environment and the host relationship. The understanding of epidemiology has a major impact on their prevention and treatment. The aim of the study is to determine the prevalence pattern of aetiological agents and to describe the clinical characteristics of dermatophytoses between 1999 and 2019. Out of 65 059 subjects suspected to have superficial mycoses, 36 220 (55.67%) were affected with dermatophytoses. The mean age was 40.1 years (range: 10 days to 99 years). The sex ratio was 0.8. Our patients were from urban regions in 80.9% of cases. The most common type of infection was onychomycosis (42.64%), followed by tinea pedis (20.8%), intertrigo (18.3%), tinea corporis (8.48%) and tinea capitis (7.87%). The most isolated dermatophyte was Trichophyton rubrum (76.5%), followed by T. mentagrophytes complex (6.3%), Microsporum canis (5.8%), T. violaceum (5.3%), T. verrucosum (0.83%) and Epidermophyton floccosum (0.3%). Zoophilic agents have become more prevalent and their frequency has been increased from 6.46% in 1999 to 13% in 2019. It is interesting to note that M. canis has been on the rise since 2010 and it was the first etiological agent of tinea capitis (48%), while infections caused by T. violaceum continued to decrease from 1999 (16.2%) to 2019 (4.7%). Other dermatophytes have been rarely isolated: T. tonsurans (9 cases), T. schoenleinii (3 cases), T. soudanense (2 cases), M. fulvum (1 case), M. audouinii (1 case) and M. ferrugineum (2 cases).T. mentagrophytes var. quinckeanum was isolated from an inflammatory tinea capitis lesion in an a-3-year-old girl. T. mentagrophytes var. erinacei was isolated from the first case of tinea manuum, in-a-10-year-old girl. The same fungus was isolated from the hair and scales of the hedgehog. Our study showed significant changes in the dermatophytes spectrum in our region. The prevalence of zoophilic species increased in recent years due to people's behavioral changes with the adoption of pets and animal husbandry in urban settings. Molecular methods are often crucial that help us to refine the identification strains of dermatophytes and to identify their origin of the contamination.

Keywords: dermatophytoses, PCR-sequencing, spectrum, Sfax, Tunisia

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3143 Causal Estimation for the Left-Truncation Adjusted Time-Varying Covariates under the Semiparametric Transformation Models of a Survival Time

Authors: Yemane Hailu Fissuh, Zhongzhan Zhang

Abstract:

In biomedical researches and randomized clinical trials, the most commonly interested outcomes are time-to-event so-called survival data. The importance of robust models in this context is to compare the effect of randomly controlled experimental groups that have a sense of causality. Causal estimation is the scientific concept of comparing the pragmatic effect of treatments conditional to the given covariates rather than assessing the simple association of response and predictors. Hence, the causal effect based semiparametric transformation model was proposed to estimate the effect of treatment with the presence of possibly time-varying covariates. Due to its high flexibility and robustness, the semiparametric transformation model which shall be applied in this paper has been given much more attention for estimation of a causal effect in modeling left-truncated and right censored survival data. Despite its wide applications and popularity in estimating unknown parameters, the maximum likelihood estimation technique is quite complex and burdensome in estimating unknown parameters and unspecified transformation function in the presence of possibly time-varying covariates. Thus, to ease the complexity we proposed the modified estimating equations. After intuitive estimation procedures, the consistency and asymptotic properties of the estimators were derived and the characteristics of the estimators in the finite sample performance of the proposed model were illustrated via simulation studies and Stanford heart transplant real data example. To sum up the study, the bias of covariates was adjusted via estimating the density function for truncation variable which was also incorporated in the model as a covariate in order to relax the independence assumption of failure time and truncation time. Moreover, the expectation-maximization (EM) algorithm was described for the estimation of iterative unknown parameters and unspecified transformation function. In addition, the causal effect was derived by the ratio of the cumulative hazard function of active and passive experiments after adjusting for bias raised in the model due to the truncation variable.

Keywords: causal estimation, EM algorithm, semiparametric transformation models, time-to-event outcomes, time-varying covariate

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3142 Studies of Lactose Utilization in Microalgal Isolate for Further Use in Dairy By-Product Bioconversion

Authors: Sergejs Kolesovs, Armands Vigants

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The use of dairy industry by-products and wastewater as a cheap substrate for microalgal growth is gaining recognition. However, the mechanisms of lactose utilization remain understudied, limiting the potential of successful microalgal biomass production using various dairy by-products, such as whey and permeate. The necessity for microalgae to produce a specific enzyme, β-galactosidase, requires the selection of suitable strains. This study focuses on a freshwater microalgal isolate's ability to grow on a semi-synthetic medium supplemented with lactose. After 10 days of agitated cultivation, an axenic microalgal isolate achieved significantly higher biomass production under mixotrophic growth conditions (0.86 ± 0.07 g/L, dry weight) than heterotrophic growth (0.46 ± 0.04 g/L). Moreover, mixotrophic cultivation had significantly higher biomass production compared to photoautotrophic growth (0.67 ± 0.05 g/L). The activity of β-galactosidase was detected in both supernatant and microalgal biomass under mixotrophic and heterotrophic growth conditions, showing the potential of extracellular and intracellular mechanisms of enzyme production. However, the main limiting factor in this study was the increase of pH values during the cultivation, significantly reducing the activity of the β-galactosidase enzyme after 3rd day of cultivation. It highlights the need for stricter control of growth parameters to ensure the enzyme's activity. Further research will assess the isolate's suitability for dairy by-product bioconversion and biomass composition.

Keywords: microalgae, lactose, whey, permeate, beta-galactosidase, mixotrophy, heterotrophy

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3141 Rheometer Enabled Study of Tissue/biomaterial Frequency-Dependent Properties

Authors: Polina Prokopovich

Abstract:

Despite the well-established dependence of cartilage mechanical properties on the frequency of the applied load, most research in the field is carried out in either load-free or constant load conditions because of the complexity of the equipment required for the determination of time-dependent properties. These simpler analyses provide a limited representation of cartilage properties thus greatly reducing the impact of the information gathered hindering the understanding of the mechanisms involved in this tissue replacement, development and pathology. More complex techniques could represent better investigative methods, but their uptake in cartilage research is limited by the highly specialised training required and cost of the equipment. There is, therefore, a clear need for alternative experimental approaches to cartilage testing to be deployed in research and clinical settings using more user-friendly and financial accessible devices. Frequency dependent material properties can be determined through rheometry that is an easy to use requiring a relatively inexpensive device; we present how a commercial rheometer can be adapted to determine the viscoelastic properties of articular cartilage. Frequency-sweep tests were run at various applied normal loads on immature, mature and trypsinased (as model of osteoarthritis) cartilage samples to determine the dynamic shear moduli (G*, G′ G″) of the tissues. Moduli increased with increasing frequency and applied load; mature cartilage had generally the highest moduli and GAG depleted samples the lowest. Hydraulic permeability (KH) was estimated from the rheological data and decreased with applied load; GAG depleted cartilage exhibited higher hydraulic permeability than either immature or mature tissues. The rheometer-based methodology developed was validated by the close comparison of the rheometer-obtained cartilage characteristics (G*, G′, G″, KH) with results obtained with more complex testing techniques available in literature. Rheometry is relatively simpler and does not require highly capital intensive machinery and staff training is more accessible; thus the use of a rheometer would represent a cost-effective approach for the determination of frequency-dependent properties of cartilage for more comprehensive and impactful results for both healthcare professional and R&D.

Keywords: tissue, rheometer, biomaterial, cartilage

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